Eggs of western Nearctic Acroneuriinae (Plecoptera: Perlidae)

2011·1.3 MB·

by  Stark, Bill P

Stark, Bill P. and Stephen Green. 2011. Eggs of western Nearctic Acroneuriinae (Plecoptera: Perlidae).
Illiesia, 7(17):157-166. Available online: http://www2.pms-lj.si/illiesia/Illiesia07-17.pdf

EGGS OF WESTERN NEARCTIC ACRONEURIINAE
(PLECOPTERA: PERLIDAE)

Bill P. Stark1 and Stephen Green2

1,2 Box 4045, Department of Biology, Mississippi College, Clinton, Mississippi, U.S.A. 39058
1 E-mail: [email protected]
2 E-mail: [email protected]

ABSTRACT
Eggs for western Nearctic acroneuriine species of Calineuria Ricker, Doroneuria Needham & Claassen and
Hesperoperla Banks are examined and redescribed based on scanning electron microscopy images taken from
specimens collected from a substantial portion of each species range. Within genera, species differences in egg
morphology are small and not always useful for species recognition, however eggs from one population of
Calineuria are significantly different from those found in other populations and this population is given
informal recognition as a possible new species.

Keywords: Plecoptera, Calineuria, Doroneuria, Hesperoperla, Egg morphology, Western Nearctic

INTRODUCTION occur in the region (Baumann & Olson 1984;
Scanning electron microscopy (SEM) is often used Kondratieff & Baumann 2002; Stark 1989; Stark &
to elucidate chorionic features for stoneflies (e.g. Gaufin 1976; Stark & Kondratieff 2004; Zuellig et al.
Baumann 1973; Grubbs 2005; Isobe 1988; Kondratieff 2006). SEM images for eggs of the primary western
2004; Kondratieff & Kirchner 1996; Nelson 2000; acroneuriine genera, Calineuria Ricker, Doroneuria
Sivec & Stark 2002; 2008; Stark & Nelson 1994; Stark Needham & Claassen and Hesperoperla Banks include
& Szczytko 1982; 1988; Szczytko & Stewart 1979) and single images for each of these genera in Stark &
Nearctic Perlidae were among the earliest stoneflies Gaufin (1976), three images of Hesperoperla hoguei
to be studied with this technique (Stark & Gaufin Baumann & Stark (1980) and three images of H.
1976). Unfortunately, the latter study is limited in pacifica (Banks) in Isobe (1997). In this study, we
sample size and in image quality. More recently, eggs examine specimens from populations with available
of many eastern Nearctic Perlidae have been egg samples for each of the five western Nearctic
examined, or re-examined, greatly increasing the acroneuriine species. Terminology follows Stark &
number of species studied and improving the image Szczytko (1988) except in the designation of anterior
quality for species known from this region (e.g. and posterior poles, where Zwick (1982) is followed.
Kondratieff & Kirchner 1996; Stark 2004; Stark &
Lentz 1988), however eggs of the primary western MATERIALS AND METHODS
Nearctic Acroneuriinae have not recently been re- Eggs were dissected from female specimens
examined. archived in 80% ethanol, cleaned manually with fine
The primary western North American tipped forceps, fine dissecting needles and dental
acroneuriine stonefly fauna includes only three brushes and sonicated for 10-20 seconds to remove
genera and five species of Perlidae, although a few extra-chorionic membranes. Cleaned eggs were
representatives of primarily eastern (Perlesta, picked up with fine tip forceps, allowed to air dry
Acroneuria) or southern genera (Anacroneuria) also and placed on specimen stubs covered with double
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Stark, Bill P. and Stephen Green. 2011. Eggs of western Nearctic Acroneuriinae (Plecoptera: Perlidae).
Illiesia, 7(17):157-166. Available online: http://www2.pms-lj.si/illiesia/Illiesia07-17.pdf

stick copper tape. Stubs were sputter coated with College, Clinton, Mississippi (BPS), the Monte L.
gold-palladium and examined with an Amray 1810 Bean Life Science Museum, Brigham Young
scanning electron microscope equipped with an University, Provo, Utah (BYU), or in the C.P. Gillette
Orion digital imaging system. Specimens used in the Museum, Colorado State University, Fort Collins,
study are archived in the Stark collection, Mississippi Colorado (CSU).

Figs. 1-4. Calineuria californica eggs, Montana, Lincoln Co., Yaak River. 1. Egg, lateral aspect. 2. Collar end. 3.
Collar end with anchor. 4. Anterior end.

RESULTS AND DISCUSSION Creek, Hwy 70, 20 May 1982, B. Stark, D. Ziegler, 1♀
(BPS). Sierra Co., Little Truckee River, Little Truckee
Calineuria californica (Banks) Campground, 4 July 1979, B. Stark, K.W. Stewart,
(Figs. 1-4) 18♂, 3♀ (BPS). Montana: Lincoln Co., Yaak River,
Yaak River Campground, 19 July 1979, B. Stark, K.W.
Perla californica Banks, 1905:87. Holotype ♀ (Museum of Stewart, R.W. Baumann, 2♀ (BPS). Oregon: Union
Comparative Zoology), Claremont [Los Angeles Co.], Co., Grande Ronde River, Hwy 244, 29 May 2000, B.
California Stark, I. Sivec, M. Zúñiga, 3♂, 4♀ (BPS).

Egg. Outline oval with short stalked collar, ends
Material examined. California: Butte Co., Heinz
broadly rounded (Fig. 1). Length including collar ca.
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Stark, Bill P. and Stephen Green. 2011. Eggs of western Nearctic Acroneuriinae (Plecoptera: Perlidae).
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430-460 μm, equatorial width ca. 360-390 μm, collar 440 μm, equatorial width ca. 372 μm. Chorionic
length ca. 35-40 μm, collar width at midlength ca. 60- surface without punctations or obvious follicle cell
68 μm. Egg body at base of collar encircled by impressions (Figs. 6, 8). Micropylar row subequatorial;
slightly raised ridge. Sides of collar with irregular, micropylar orifices with raised rims (Fig. 7).
prominent struts (Fig. 2); rim flanged and irregularly Comments. Eggs of C. californica (Figs. 1-4) and the
incised (Figs. 1-2). Anchor biscuit-shaped, surface three species of Japanese Calineuria (Isobe 1988; 1997)
with scattered mushroom bodies (Fig. 3). Chorionic have similar short stalked collars encircled by a low
surface relatively smooth but with obscure hexagonal to well developed basal ridge. The chorionic surface
follicle cell impressions visible at 500X (Figs. 2, 4). is punctate in the Japanese species but smooth or
Micropylar row subequatorial. with obscure follicle cell impressions in C. californica
and C. sp. A (Figs. 2, 6). The male and female of C.
Calineuria sp. A sp. A appear indistinguishable from C. californica in
(Figs. 5-8) color pattern, subgenital plate shape and aedeagal
armature, however, the egg has no collar. These
Material examined. California: Marin Co., Muir specimens may represent an undescribed species, but
Woods, Redwood Creek, 21 June 1985, B. Stark, 1♀ a larger sample and a comprehensive study of other
(BPS). Same location, 18 June 1966, R.W. Baumann, Calineuria specimens is needed in order to evaluate
1♂, 1♀ (BYU). its status. Drumming and molecular data may also be
Egg. Outline oval, collar absent (Fig. 5). Length ca. desirable.

Figs. 5-8. Calineuria sp. A eggs, California, Marin Co., Redwood Creek, Muir Woods. 5. Egg, lateral aspect. 6.
Collar end. 7. Micropyle. 8. Anterior end.
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Stark, Bill P. and Stephen Green. 2011. Eggs of western Nearctic Acroneuriinae (Plecoptera: Perlidae).
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Doroneuria baumanni Stark & Gaufin Washington: Pierce Co., Carbon River, 16 August
(Figs. 9-12) 1999, B.C. Kondratieff, 1♂, 3♀ (BPS).
Egg. Outline oval with short, narrow collar (Fig.
Doroneuria baumanni Stark & Gaufin, 1974:88. Holotype 9). Egg length ca. 500 μm, equatorial width ca. 400
♂ (United States National Museum), Burney Falls State μm, collar length ca. 20 μm, width ca. 50 μm.
Park, Shasta Co., California Chorionic surface coarsely punctate with shallow

pits over middle half of egg (Figs 10, 12. );
Material examined. California: Siskiyou Co., Big
punctate zone ca. 260 μm wide; area around collar
Springs, Mt. Shasta City Park, 7 July 1979, B. Stark,
and a narrow opercular ring around lid lack pits;
K.W. Stewart, 1♀ (BPS). Oregon: Benton Co., Kiser
some pits on lid form obscure follicle cell
Creek, Hwy 39, 1 June 2000, B. Stark, I. Sivec, M.
impression walls. Micropylar row located on lid
Zúñiga, 3♂, 1♀ (BPS). Multnomah Co., Wahkeena
(Fig. 11); orifices raised, canals not clearly visible
Falls, 25 June 1985, B. Stark, 24♂, 4♀(BPS).
on surface.

Figs. 9-12. Doroneuria baumanni eggs, Oregon, Multnomah Co., Wahkeena Falls. 9. Egg, lateral aspect. 10.
Collar end. 11. Micropyles. 12. Anterior end.

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Doroneuria theodora (Needham & Claassen) opercular band surrounding lid. Lid with obscure,
(Figs. 13-16) irregularly shaped follicle cell impressions, but
punctations absent (Fig. ). Micropylar row located on
Acroneuria (Doroneuria) theodora Needham & Claassen, lid; orifices raised, canals obscure (Fig. 15).
1922:254. Holotype ♀ (Cornell University), Yellowstone Comments. Eggs of Doroneuria are large, oval, and
National Park, Wyoming have small collars. The chorionic surface has a broad
median zone of shallow pits, a narrow smooth
Material examined. Montana: Gallatin Co., Hyalite opercular band and micropyles located on the lid
Creek, above Window Rock, 20 August 2004, B. near the anterior pole (Figs. 9, 13). The eggs of the
Stark, I. Sivec, 1♀ (BPS). Wyoming: Johnson Co., two species are quite similar, but differ subtly among
Middle Fork Clear Creek, 17 August 2004, B. Stark, I. specimens examined in two respects. The punctate
Sivec, 2♂, 2♀ (BPS). Park Co., Lake Creek, Hwy 296, zone for D. theodora eggs extends nearer the collar
18 August 2004, B. Stark, I. Sivec, 3♂, 3♀ (BPS). and is, therefore, considerably broader in that species
Egg. Outline oval with short, narrow collar (Fig. 13). than in D. baumanni (Figs. 10, 14). In addition, the lid
Egg length ca. 530 μm, equatorial width ca. 400 μm, of D. theodora eggs lacks punctations, whereas in D.
collar length ca. 30 μm, width ca. 60 μm. Chorionic baumanni this area has obscure punctations which
surface coarsely punctate in a band ca. 325 μm wide, outline the irregular margins of follicle cell
extending from near collar (Figs. 14, 16) to smooth impressions (Fig. 12).

Figs. 13-16. Doroneuria theodora eggs, Wyoming, Johnson Co., Middle Fork Clear Creek. 13. Egg, lateral aspect.
14. Collar end. 15. Micropyles. 16. Anterior end.
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Stark, Bill P. and Stephen Green. 2011. Eggs of western Nearctic Acroneuriinae (Plecoptera: Perlidae).
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Hesperoperla hoguei Baumann & Stark Egg. Outline oval with short, wide collar (Fig. 17);
(Figs. 17-20) collar base encircled by prominent raised ridge, sides
of egg body adjacent to ridge with a series of vertical
Hesperoperla hoguei Baumann & Stark, 1980:63. struts. Egg length ca. 400 μm, equatorial width ca.
Holotype ♂ (Natural History Museum, Los Angeles 360 μm, collar length ca. 50 μm, median width ca. 75
County), Gibson Creek, Mendocino Co., California μm. Sides of collar with several prominent
longitudinal ridges (Fig. 19); collar rim flanged and
Material examined. California: Plumas Co., irregularly incised (Figs. 18, 20). Anchor biscuit
Domingo Springs, 8 miles NW Chester, Old Red shaped with moderately long pedicel; surface
Bluff Road, 21 September 2007, J. Sandberg, 2♂, 5♀ covered with mushroom bodies. Chorionic surface
(BPS). Sierra Co., Big Spring, Hwy 49, 2 miles N covered with shallow, hexagonal follicle cell
Bassetts, 3 July 2010, P.A. Opler, 1♀ (CSU). impressions. Micropylar row subequatorial.

Figs. 17-20. Hesperoperla hoguei eggs, California, Sierra Co., Big Spring, Hwy 49, 2 miles north Bassetts. 17. Egg,
lateral aspect. 18. Egg, apical aspect. 19. Collar end. 20. Collar detail, apical aspect.

Hesperoperla pacifica (Banks) Acroneuria pacifica Banks, 1900:242. Holotype ♀
(Figs. 21-30) (Museum of Comparative Zoology), Olympia
[Thurston Co.], Washington
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Material examined. Alberta: Battle Creek at Mexico: San Miguel Co., Pecos River, 6 miles north
Reservoir Lake, 23 June 1975, L. Dosdall, 1♀ (BPS). Pecos, 12 July 1973, B. Stark, 2♂, 3♀(BPS). Nevada:
California: Humboldt Co., East Fork Willow Creek, Elko Co., Secret Creek, Secret Pass, 15 June 1974, B.
Hwy 299, 24 April 1987, B. Stark, R.W. Baumann, Stark, 1♂, 1♀(BPS). Oregon: Jefferson Co., Metolius
C.R. Nelson, 2♀(BPS). Shasta Co., North Fork Battle River at headwater spring source, 11 July 1979, B.
Creek, south of Shingletown, 8 June 2004, B. Stark, Stark, K.W. Stewart, 5♂, 3♀ (BPS). Tillamook Co.,
R.W. Baumann, 1♀(BPS). Tehama Co., North Fork Nehalem River at Cronin Creek jct., 4 June 1991, B.
Battle Creek, Wildcat Road, 26 April 1987, B. Stark, Stark, R.W. Baumann, C. Henderson, 1♀(BPS).
R.W. Baumann, C.R. Nelson, 2♀ (BPS). Colorado: Wyoming: Park Co., Clarks Fork Yellowstone River,
Gunnison Co., Gunnison River, Hwy 135, 8 June below Cooke City, 20 July 1989, B. Stark, 3♂, 1♀ (BPS).
2003, B. Stark, 3♂, 2♀ (BPS). Idaho: Bonneville Co., Egg. Outline oval with short, wide collar (Fig. 21);
Snake River, 4 July 1972, G. Tourtlotte, 1♂, 1♀(BPS). collar base encircled by a prominent basal ring, ca.
Fremont Co., Big Springs, 5 miles east Macks Inn, 25 137-176 μm wide (Figs. 23, 25, 27, 29); sides of egg
July 1979, B. Stark, K.W. Stewart, R.W. Baumann, 4♀ body along basal ring bearing a series of vertical
(BPS). Montana: Carbon Co., East Rosebud River, ridges separated by wide depressions. Egg length ca.
Roscoe, 23 July 1989, B. Stark, 5♂, 3♀ (BPS). Lewis & 428-484 μm, equatorial width ca. 312-324 μm, collar
Clark Co., Trout Creek, Vigilante Campground, 21 length ca. 34-55 μm, median collar width ca. 41-58
August 2004, B. Stark, I. Sivec, 1♂, 1♀(BPS). New μm, rim width ca. 89-116 μm. Sides of collar with

Figs. 21-24. Hesperoperla pacifica eggs, Idaho, Bonneville Co., Snake River. 21. Egg, lateral aspect. 22. Egg, apical
aspect. 23. Collar end. 24. Micropyles.
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Figs. 25-30. Hesperoperla pacifica eggs. 25-26. Colorado, Gunnison Co., Gunnison River. 25. Collar end. 26.
Anterior end. 27-28. Montana, Lewis & Clark Co., Trout Creek. 27. Collar end. 28. Anterior end. 29-30.
Oregon, Jefferson Co., headwaters Metolius River. 29. Collar end. 30. Anterior end.

several prominent vertical ridges, rim flanged and smooth (Figs. 21, 26, 28, 30) but with obscure
irregularly incised. Chorionic surface appearing hexagonal follicle cell impressions sometimes
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apparent at higher magnifications. Micropyles description of a new species from Arizona.
located near equator; orifices raised slightly (Fig. 24). Southwestern Naturalist, 29:489-492.
Comments. Hesperoperla eggs are generally similar to Baumann, R.W. & B.P. Stark. 1980. Hesperoperla
those of Calineuria californica in shape, collar form hoguei, a new species of stonefly from California
and in having a basal ridge encircling the collar base (Plecoptera: Perlidae). Great Basin Naturalist,
(Baumann & Stark 1980; Isobe 1997). The most 40:63-67.
conspicuous feature distinguishing the eggs of the Grubbs, S.A. 2005. Perlesta shawnee (Plecoptera:
two genera is the row of vertical struts on the egg Perlidae), a new stonefly species from eastern
body which connect to the basal ridge in Hesperoperla North America. Aquatic Insects, 27:63-69.
(Fig. 25) which are absent in eggs of Calineuria (Fig. Isobe, Y. 1988. Eggs of Plecoptera from Japan.
2). No consistent morphological differences were Biology of Inland Waters, 4:27-39.
found among eggs of different populations of H. Isobe, Y. 1997. Anchors of stonefly eggs. pp. 349-361.
pacifica, or between eggs of H. hoguei and H. pacifica. In Landolt, P. & M. Sartori [eds.]. Ephemeroptera
However, variations are evident in the images of H. & Plecoptera: Biology-Ecology-Systematics.
pacifica eggs from different sites (Figs. 21-30), Mauron, Tinguely & Lachat Publishers, Fribourg,
especially in shape of the anterior pole (e.g. Figs. 26, Switzerland.
28), shape of the collar (e.g. Figs. 25, 27) and in length Kondratieff, B.C. 2004. Perlodidae – Perlodinae (The
of lines delimiting cells surrounding the basal ridge Springflies). pp. 149-180. In Stark, B.P. & B.J.
(= vertical struts). The specimen shown from the Armitage [eds.]. Stoneflies (Plecoptera) of eastern
Gunnison River, Colorado, for example, has a few North America. Volume II. Chloroperlidae,
long lines of at least 57 μm (Fig. 25), whereas the Perlidae, and Perlodidae (Perlodinae). Bulletin of
longest vertical struts on the specimen shown from the Ohio Biological Survey, New Series, Volume
Trout Creek, Montana (Fig. 27) are only 30 μm. 14. Ohio Biological Survey, Columbus, Ohio. 192
pp.
ACKNOWLEDGMENTS Kondratieff, B.C. & R.W. Baumann. 2002. A review of
We thank Richard W. Baumann, Monte L. Bean the stoneflies of Colorado with description of a
Life Science Museum, Brigham Young University new species of Capnia (Plecoptera: Capniidae).
and Boris C. Kondratieff, Department of Bioagricultural Transactions of the American Entomological
Sciences and Pest Management, Colorado State Society, 128:385-401.
University, for the loan of specimens used in this Kondratieff, B.C. & R.F. Kirchner. 1996. Two new
study. John B. Sandberg, California Department of species of Hansonoperla (Plecoptera: Perlidae)
Fish and Game and California State University at from eastern North America. Annals of the
Chico graciously provided a series of Hesperoperla Entomological Society of North America, 89:501-
hoguei specimens. 509.
Needham, J.G. & P.W. Claassen. 1922. The North
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